Testing-circuit



J. F.'T00MEY. TESTING cmcul;

APPLICATION FILED JUNE 2l. 1919.

Patented Nov. 30, 1920.

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kbw R k E 0 W @5L ,JA .Www s@ hij @f Q%\ JM w s@ 1 um, U sur u ATTORN EY UNITED STATES PATENT OFFICE,

JOHN r. TOOMEY, or NEW YORK, N; Y., assIGNoR TO AMERICAN TELEPHONE AND TELEGRAPH COMPANY, A CORPORATION or NEW YORK.

TESTING-CIRCUIT.

' o all whom t may concern:

Be it known that `{loi-INlTooivUiY, residing at New York, inthe county of New York and State of New York, have invented certain Improvements in TeStingCircuits, oi which the following` is a specification.

This invention relates to testing circuits, particularly circuits for testing relays at repeater installations.

Certain typesof telephone repeaters present so high an impedance to currents of the frequencies ordinarily employed `for ringing that it is necessary to provide separate apparatus for relaying the ringing current around` the repeater installation. This re laying apparatus. comprises, generally, a relay associated with `the section of the line on-one side of the repeater and responsive to ringing current in said section, Which r`elay controls a ringing relay associated with the section of the line on the other sideof the repeater and adapted to apply ringing current to said section Whenthe first-mentioned relay is energized by ringing current in. its section. provided for relaying the ringing current in the opposite direction. This relaying apparatus is subjected to frequent tests, for if its fails to operate properly it is usually impossible to ring over the line.

It is the object ot this invention to provide a testing circuit and apparatus by means of which these tests may be made eX- peditiously and accurately, Without causing any interruption in a conversation that may be in progressat the time of the test, or causing a false ring over the line.

The manner in` which the above objects and advantages are attained by this invent-ion Will be readily understood from the following description thereof, considered in connection with the accompanying drawing showing in diagrammatic Jformone arrangement of apparatus and circuits embodying the invention.

In this drawing reference charactn` L` designates a transmission line,the conductors of the `east and west sections of whichA section of the line to theother, which apparatus comprises a relay 4i associated with `the east section of the line by means of the Application led June 21, 1919. Serial No. 305,718.`

A y similar arrangement is` speciacation of Lederwaren/c. Patented Nowg, 1920,`

tip and ring contacts of a jacko. lelayt controls a relay 6, 'which is" normally ener;

gizedby current 'i'roln a battery 7, and re- `in the east section of the line,` it causes `the energizatifon of` relay 4f, which relay opens its contactand thus causes relay G to close the circuit ofrelay 3a. This relay is energized and closes its front contacts and thus applies ringing current to the West section of the line. The apparatus above described `thus relays ringing current 'from east to vvest, `and like apparatus` is employed. `ior relaying the ringing `current in the opposite direction, this apparatus comprising relays 426 and. ,i f y l A testing circuit T isprovided for test ing the relay apparatus above described, a patching cord 15 and jacks 5 and 16 serv ing to associate this circuit with `thesaid apparatus. The tip and ringcontacts of jack 5 connecting the relay fl `with the east section ofthe line are broken when the plug of cord isinserted in the jack 5, the cir;- cuit of the relay novv` extending from a source of ringing current in the testing circuit, throughthe contacts of alrelay 17, through the tip` and ring of jack `16 and the tip and ring conductors y of the patching cord 1.5` to fthe Winding of the relay. VThe circuit of relay 17 is` governeduby keys 1S and`19 in a portablecontrol box` notshovvii, which keys may be associated with the test;` ingcircuit by means of a `plug andjackQO, the circuitof the relay 17 extending from a battery 21 through 4,the Winding of marginal relay" 22 and the windingoit relay'l, through the tip contact ofjack`20keys 18 and19 in parallel and through the `sleeve e contact of jack 20 to ground. W'henkey 18 isclosed the current from, battery` 21 is sufficient to energize both relays 22 and 17 and when key 19 is depressed the "current is so limited by a resistancef25 in series with the key that themarginal relay`22 fails toop# `erate`.,` Relay 17,` therefore, `responds to eitherkey but relay 22 only to key 18.` The relay 22 controls a` contact which, when closed, short circuits a resistance 26 connected in series 'Withanother resistance 27 Y Vjustment, responds in one casel but not in the other. In other-Words, relay 4 should open its contact When theoperator depresses key 19, but not when he depresses key 18.'

. To prevent a false application of signaling current'to the West vsection of the line, whenV relay 4 is" thus operated, relay 3f* is rendered unresponsive to rrelay 6 by connecting a relay 30 in series Wit-h relay 3, the circuit thereof novv extending from battery 10? through the Winding of relay 3, conductor 11, contactofrelay, conductor 12, sleevecontacts of jacks 5' and 16, relay 30 to ground. The resistance of relay 30 is such that the current from battery 10iL is too Weak to causean operation of relay 3a, although sufficient to operate relay 30, this relay beingrarranged to attracty its armature When traversed by only a small current. The Vcontact of relay 3() controls a circuit extending -from battery 31 through the contact Yof relay 30, conductor 32, ring contact of Ajackf20, anI indicating. lamp 34 in the portablek control box, and the sleeve of jack 20 to. ground. :Lamp 34 is thus caused' to `indicate the operationrof relays 4 and 6.

The operation of relays 42L and-6a may be observed :i-nlike manner by associating the testing circuit with 'j ack 5a.

The testing operationv vis readilyunderstood from the foregoing description of the circuits. .The operator merely associates the testing circuit with the jackV ofthe relays under test and With the plug of the portable controlbox. V,He then depresses keys 18 and 19 consecutively. If the relays 4 and 6 are properly adjusted,- lamp 34 remains dark `When key`18 operated, lights When'key 19 is depressedandgoesoutV When key 19 is released., e

Onefof the main features of this invention resides'in the fact that one man, alone, may make thetest, Whereas in the arrangements lheretofore lused tivo men/Were required.

The relay jacks and 5? are located at the relay racksand the jacks 16 and 2O of the testing circuit are brought out in multiples near thev relay jacks, Vso that the operator may observe the action ofthe relay armatures and contact springs `When he actuates the keys'f18 Vand 19 of the portable control b ox, and thus determines Where-the trouble lies when 'the indicating lamp inv the box fails to'respond properly tothe control keys,

Although only one form of apparatus and circuit embodying the invention is shown and described herein, it is readily understood that various changes and modifications may be made therein Within the scope of the following claims Without departing from the spirit and scope of the invention.

What is claimed is:

1. ln combinatione a line, a relay responsive to ringing current in said line, a second relay responsive to said first relay for applying ringing` current to said line, means for applyingtesting current to said first relay, an indicating device and means operative when said first mentioned means is associated with said relay for renderingr said second relay unresponsive and said indicating device responsive to said first relav.

9J. ln combination, a transmission line comprising two sections, means responsive to ringing current in one section of said line for applying ringing current to the other section thereof, a source of test-ing current. means for associating said source with said first mentioned means, an indicating device, and means for rendering said first mentioned means inoperative to apply current to said other section and for rendering said indicating device responsive to said first mentioned means.

' ln combination, a first relay, a source of test-ing current therefor, a second relay. a

circuit for controlling the second relay b v the first relay, a third relay responsive to less current than said second relay, means operative when said source is associated with said first relay for connecting said third relay in series with the circuit of said second relay1 whereby the third relay is rendered responsive and the second relay unresponsive to said first relay.

4. In combination, a line, a relay responsive to ringing current in said line, a second relay responsive to said first relay, a source of ringing current, a third relay responsive to said second relay for associating said source with said line, a testing circuit for said first and second relays comprising a source of ringing current, means for associating said circuit with the first mentioned relay and dissociating said relay from said line, an indicating device, means for governing said device by said first and second relays and means associated with said testing circuit for governing the amount of current supplied to said first relay from said source in said testing circuit.

5. In combination, a line, a relay responsive to ringing current in said line, a source of ringing current, a second relay for associating said source with said line, a source of testing current for said relays, means for associating said source with said first relay and dissociating said relay from said line, a translating device, means operative when lll() said first relay is energized by testing current for rendering said translating device responsive to said first relay and said second rela unresponsive thereto, means for control'ing the amount of testing current applied to said first relay, and an indicating device controlled by said translating device.

` associated with said jack for connecting sai d fourth relay in series with said. third relay and thus rendering said third relay unresponsive to said second relay and said fourth relay responsive thereto, an indicating deiice responsive to said fourth relay, a plu rality of controlling lieys7 and a relay selectively controlled loy said lreys for controlling the amount of testing current associated with said first relay.

7. A device `iortesting the translating apparatus for relaying ringingcurrent from one section of a transmission line to another, the said translating apparatus comprising a tlrst relay responsive to ringing current in one section of the line and a second relay responsive to the first for associating ringing current with the other section of the line; said device comprising a source of testing current, a portable controlling apparatus and means associated therewith for causing a normally operative or an inoperative amount of current from said source to traverse said rst relay, means for renden ing said second relay nonresponsive to said first when the same is actuated hy testing current, and an indicating device associated with said portable apparatus for indicating the response of said first relay to said testing current.

S. A device for testing the apparatus for relaying ringing current from one section of a transmission line to another, about a repeater normally associating said sections of the line for current of other than ringing frequency, said relaying apparatus being arranged, when operating, to dissociate the repeater and the line; said device comprising means for associating testing current with said relaying apparatus, means for preventing said relaying apparatus from dissociating the repeater and the line during the test, an indicating device, and means for causing said device to indicatethe response of said relaying apparatus to said testing current. 4

In testimonyT whereof, l. have signed my naineto this speciication this 20th day of JOHN F. TOOMEY.

. June, 1919. 

